Three new coordination polymers (CPs) of coordinated isoniazid (INH) to Zn(II) with succinic acid (H 2 succ), fumaric acid (H 2 fum), and terephthalic acid (H 2 bdc) as organic linker, [Zn(INH)(succ)] n (1), [Zn(INH)(fum)] n (2), and [Zn(INH)(bdc)] n (3), respectively, have been characterized. The structure determination by the single crystal X-ray diffraction technique shows a ZnN 2 O 4 distorted octahedral geometry, and the 1D chain is constituted via the INH and carboxylate coordination along with the hydrogen bonding (N−H•••O) which comprises a 2D structure. The CPs, 1 and 2, are isostructural and fabricate supramolecular networks by inclined intercatenation of two 2D layers, while 3 shows parallel intercatenation. The electrical conductivity and Schottky barrier diode behavior have been established by the charge transport mechanism of the compounds at the quasi-Fermi level state. The analysis indicates that the compound 1 has the highest mobility (2.53 × 10 −10 m 2 V −1 s −1 ) than 2 (1.86 × 10 −10 m 2 V −1 s −1 ) and 3 (1.89 × 10 −10 m 2 V −1 s −1 ) and the highest electrical conductivity (2.26 × 10 −4 S m −1 ) than the others (1.12 × 10 −4 S m −1 (2) and 1.25 × 10 −4 S m −1 (3)). DFT computation of the structural motif of CPs has calculated the band gap (ΔE: 3.93 eV (1), 4.45 eV (2), 4.26 eV (3)), which supports the progression of conductivity.

On account of the easy functionality and structural diversity, coupled with superior thermal stability of coordination polymers (CPs), many researchers prompted to explore the opportunity of introducing these hybrid materials...

Four new mixed-ligand divalent coordination polymers (CPs) [Cu2­(muco)2­(4-clpy)2] (1), [Cu2­(muco)2­(4-brpy)2] (2), [Zn2­(bdc)2­(4-clpy)2] (3), and [Zn2­(bdc)2­(4-brpy)2] (4) (H2muco = trans,trans-muconic acid or 1,3-butadiene-1,4-dicarbox­ylic acid; H2bdc = 1,4-benzene dicarbox­ylic acid; 4-clpy = 4-chloro­pyridine and 4-brpy = 4-bromo­pyridine) have been synthesized and well characterized by elemental analysis, infrared spectra, single-crystal X-ray diffraction techniques, powder X-ray diffraction patterns, and thermogravimetric analysis. All the compounds 1–4 have a two-dimensional (2D) coordination polymeric sheet structure. Of these, 1 and 2 are isotypical and form a 3D supramolecular aggregation based on type-I halogen–halogen interactions (Cl···Cl or Br···Br) and have an impact on CO2 sorption properties. For the first time, halogen–halogen interactions have been used as a tool in the construction of high-dimensional CPs for sorption studies. However, analogous compounds 3 and 4 are expanded to 3D supramolecular structures based on π···π interactions. These compounds have no halogen–halogen interactions and hence become nonporous toward CO2 sorption. It appears that the halogen–halogen interactions between the 2D sheets are desirable for the uptake of CO2 gas.

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A new Cu(ii)-based 1D coordination polymer [Cu(fum)(4-phpy)2(H2O)], (1) (H2fum = fumaric acid and 4-phpy = 4-phenyl pyridine) exhibits electrical conductivity in the semiconductor region and behaves as Schottky diode.